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Sierra 18-9866 Dial Indicator Holding Tool for Mercury Marine Stern Drives

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

18-9866
09/10/2036 8:20 PM
Sale Price

$15.33

1 left at this price

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-9866 Dial Indicator Holding Tool is a precision marine service tool designed to securely mount a dial indicator to the gear housing during backlash measurement procedures on Mercury Marine stern drive and outboard applications. This is a direct replacement for Mercury Marine OEM part number 91-89897.

Key Features:

  • Secures a dial indicator to the gear housing for accurate backlash measurement
  • Constructed from high-quality steel with a durable black oxide finish
  • Compatible with TR, TRS, MC-I, R-MR, and Alpha One stern drive units and outboards
  • Meets or exceeds manufacturer's recommended specifications
  • Backed by Sierra's limited lifetime warranty

Replaces OEM Part Numbers:

  • Mercury Marine: 91-89897

The Sierra 18-9866 is an essential tool for marine technicians and experienced DIY mechanics performing gear backlash inspection and adjustment on Mercury Marine stern drives. Sierra Marine's service tools are engineered to OEM standards, ensuring reliable, accurate results during critical drivetrain service procedures.

they had the part, decent price, Amazon checkout is very convenient UPDATE: I was really impressed that the item came 2 days later!!! I was anticipating a week at the least.. ordered Thursday and delivered Saturday _AWESOME

I hope its the correct part!

FB

good price

VERY GOOD

very user friendly - now I just need to see the product!

Very easy transaction.

quick and easy

so far so good

Great price

Great prices and fast shipping.

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